One of the main problems existing today in the sector of sealing systems for vessels subjected to high pressure is the existing limitation when it comes to finding a sealing system which confers an optimum sealing while at the same time a prolonged service life due to the fact that there is no material having the properties intended to fulfill said needs arising from the task to be performed by the sealing.
It has been considered until now that the best option is to use a high strength material with a low Young's modulus so that it can be easily expanded for closing the existing gap with the high pressure vessel, making the stresses generated in the gasket the lowest possible, for which in some cases adding an anti-friction coating to reduce the damage which can be suffered by the vessel has been considered.
These anti-friction treatments render anti-friction characteristics to the part with which the friction is produced; there being the problem that, upon opening and closing the vessel for loading the product, since water is used as the pressurizing means for the high pressure vessels, it eliminates the anti-friction characteristics of the actuation area, with the subsequent problem of having to find a material which, in addition to having a prolonged fatigue life, provides the sealing with favorable properties such as a low Young's modulus so that the operation of the metal ring is favorable so that the polymer gaskets work upon closing the gap with the high pressure vessel, an excellent fracture toughness so that its life is prolonged, a high mechanical strength for supporting high stresses due to the ultrahigh pressures and a low coefficient of friction with stainless steel for reducing the friction of the vessel-contacting surface of the ring, since the support rings which have been used until now frequently fail due to fatigue, causing irreparable damage to the high pressure vessels to be sealed with their breakages.
Some documents, such as Spanish document no. ES0282924-U, describes a high pressure vessel with inner closing wherein an obturating ring divided into two sections which acts by means of wedging is different, the two-part arrangement of the ring being intended for functions different from the functions of conferring specific properties to obtain the advantages indicated by the double sealing ring, therefore it would not solve the problem described.
There is also another document no. WO2007/020099-A2 describing a sealing gasket with a metal support ring with a coating to reduce the friction and two polymer seals, said ring not being divided into two or more differentiated parts of different materials, and said ring having a different configuration with different effects.